Hidden Solar Cycle Could Reshape Space Weather for the Next 50 Years, Finds Study

The Gleissberg Cycle, named after the German astronomer Wolfgang Gleissberg, helps to explain why space weather is projected to get more intense in the following decades. More sunspots, flares, and coronal mass ejections result from the sun's twisted magnetic field in this cycle. The proton soup surrounding Earth will get denser as solar cycle 25 wanes and passes. Long-term observations of the sun's continuous active character suggest more high-energy protons and hint towards Earth's atmosphere getting hotter.

Hidden Solar Cycle Awakens, Fueling Surging Solar Activity

As per the new study, the unexpected surge of solar activity during the ongoing solar maximum may be tied to a lesser-known, 100-year-long cycle that is just beginning to ramp up again. The findings could lead to further increases in solar activity that may threaten Earth-orbiting spacecraft and continue to trigger vibrant auroras across the globe. Influenced by periodic solar activity patterns, the 11-year solar cycle is said to be a natural fluctuation in the activity of our home star that spans a tranquil solar minimum to a chaotic maximum, releasing severe storms at solar maximum and then returning to this condition.

Scientists believe the Centennial Gleissberg Cycle (CGC) may have resumed, therefore skewing the computation of the continuous solar maximum. NOAA satellites supplied data on proton flux from the South Atlantic anomaly.

Hidden Solar Cycle May Signal Stronger Space Storms Ahead

Auroras at the end of Solar Cycle 25 result from space weather phenomena, including a supercharged geomagnetic storm which occurred in May 2024. This unusual behaviour poses questions about the presumptions and suggests that the CGC minimum might be past. Future cycles may be as active and strong as the CGC maximum approaches, thereby perhaps affecting the sunspot cycle more than formerly believed. The radiation sensitivity of astronauts could provide challenges for private satellite mega constellations and satellites.

However, not everyone entirely agrees with the new findings. Proton flux has only gone down over the past year, so it could just be a temporary dip caused by the natural variability of the sun, the report adds. For their findings to be conclusive, the study team most likely requires some additional years of data.